Ice Nucleating Properties and Spectroscopic Analysis of Dissolved Soil Organic Matter

Evidence shows that soil organic matter (SOM) could play an important role in ice nucleation. In this study, we collected dissolved SOM after rain events at Southern Great Plains site in Lamont, Oklahoma, USA, and investigated the immersion freezing ice nucleating abilities of these soil suspended solutions at mixed-phase cloud conditions. Preliminary results show that particles generated from dissolved SOM are spherical and nucleate ice efficiently. However, after exposure to heat and H₂O₂ treatments, the particles morphology is changed and their ability to nucleate ice decreases. This presentation will highlight recent results including the chemical and morphological analysis of these particles.